Matrix setting and type-line-casting machine



Jan. 14, 1941.. K, B NDO FF 2,228,810

MATRIX SETTING AND TYPE-LINE-CASTING MACHINE Filed Aug. 15, 1939 Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE MATRIX SETTING AND TYPE-LINE-CASTING MACHINE Application August 15, 1939, Serial No. 290,303 In Germany January 28, 1938 3 Claims.

The invention relates to the key mechanism of a matrix-composing and type line-casting machine provided with electromagnetically actuated tripping devices. In such key mechanisms, it is necessary on the one hand that the contacts should be closed in a completely reliable manner at the commencement of the key movement and on the other hand that the contact closing should be independent of the further depression of the key, so that in particular even if the key is completely pressed home no flexing of the resilient electric contacts beyond the prescribed limit can take place. These conditions are also fulfilled for other purposes in the electrotechnical art, that is to say with the aid of the so-called camcontrols, but it has hitherto been impossible to employ such arrangements for this purpose in matrix-composing and type line-casting machines or the key mechanisms thereof, because in these all the parts must be so constructed as to permit of movement wtih as little friction as possible and in particular to limit to a minimum the force required to depress the key to the extent necessary to make contact in order to avoid tiring of the operator without impairing the reliability of the contact closing.

However, these conditions cannot immediately be fulfilled with the cam control arrangement known per se in the electrotechnical art. Only with the releasing key according to the invention is it possible to employ the cam control for the key mechanism of a matrix-composing and type line-setting machine for the aforesaid particular purpose, which is achieved by connecting each of the spring-loaded composing keys through a link situated at its lower end to a cam disc pivotally mounted in the key mechanism frame, the said cam disc compressing the contact springs with its concentric cam face upon depression of the key, but allowing the contact spring to return into the released inoperative position by means of its slope upon release of the key, while the equilibrium due to the symmetrical construction of the cam disc assists the work of the keyreturning spring.

A constructional example of the invention is diagrammatically shown in the accompanying drawing, in which:

Figure 1 is a side elevation of the key in the inoperative position,

Figure 2 is a front elevation thereof, and

Figure 3 is the same view as Figure 1, but showing the key partly depressed and at the commencement of its movement, after the correspondingly flexed resilient contacts have been closed.

In the key mechanism frame I rigidly connected to the machine frame, the electric contact springs 2 are secured. When all the parts are in the inoperative position corresponding to the broken circuit (Figures 1 and 2), a rotatably mounted eccentric disc, but preferably a cam contact disc 4 rotatably mounted on a pivot 3 of the key mechanism frame I, bears by means of a bearing surface 5 adapted to the contact springs against the forward end of the upper spring of each pair of contact springs. face 5 is preferably formed by a flattened part of the otherwise arcuate cam disc 4. That part of the cam disc 4 which faces upwards towards the keys 6 in the inoperative position (Figures 1 and 2) is preferably also flattened. As is shown in the drawing, a bar 7 is so articulated to this part of the cam disc 4, which is situated above the pivot 3 in the inoperative position, as to be readily rotatable, said bar being similarly connected to the key rod 8 which is longitudinally displaceably guided in the key mechanism frame I. A spring, for example a helical spring 9 surrounding the key rod 8 below the key head 6 and bearing against the frame I, constantly tends to move the key 6, 8, and thus all the parts connected thereto, in the upward direction and into the inoperative position shown in Figures 1 and 2. In order to facilitate mounting, the helical spring 5 is preferably replaced by a leaf spring (not shown) which is connected at one end to the frame I and engages at its free end with the key rod 8. Owing to the arrangement of the articulated bar 1, no friction is set up between the key rod 8 and the cam disc 4 upon depression of the key. The arrangement is such that at the beginning of the downward movement of the key 6, 8, that is to say even upon a small rotation of the cam disc 4 in the direction of the arrow A (Figure 3), the bearing surface 5 leaves the contact spring, and the contact cam 4, which is preferably of arcuate form, then presses against the contact springs 2, thus bringing them into contact with one another and deflecting them somewhat in the downward direction (Figure 3). The distance of the cam 4 from the pivot 3 of the cam disc, that is to say, the radius of the are H), is greater than the distance of the bearing surface 5 from the pivot 3 in accordance with the necessary and permissible flexing of the contact springs 2 which are to be brought into contact with one another. It will readily be understood that the compositor can feel immediately upon This bearing surstriking the keys, even though he only moves them a small distance, that he has done the work necessary for closing the circuit, that is to say, flexed the contact springs 2 to the necessary extent. The resistance to be overcome by him in this work can be felt, that is to say when, at the beginning of the movement the cam 4 encounters the bearing surface 5 and presses against the contact spring .2. With this new arrangement, the compositor is not, on the one hand, compelled to depress the key 6, 8 to the end of its stroke in order to be certain of effecting the necessary circuit closing, as is the case when the circuit is not closed until this is done, because otherwise if the key were too strongly depressed the contact springs would be warped and unreliability in the releasing of the matrix would result. On the other hand, even if the key 6, 8 is depressed to a greater extent than is necessary for closing the circuit, the contact springs 2 cannot be more greatly flexed, because when they have been brought together by the cam 4, only a displacement of the cam 4 on the upper contact spring takes place without this sprin being pressed any further downwards.

That part of the cam disc 4 which lies opposite the surface and which is not effective, that is to say is not connected to the contact springs 2, is preferably symmetrical, that is to say, is also constructed to correspond to a full disc in order thus to produce a force which counteracts the key pressure and assists the spring 9 when the key is depressed. This permits of a construction in which the moving parts alone maintain equilibrium and the spring 9 must merely have a slightly stronger action than is required for overcoming the friction between the cam contact l0 and the contact springs 2. This construction of the cam disc 4, which is found to be very advantageous, thus permits of employing particularly weak key-returning springs 9, which is necessary for avoiding tiring of the compositor which otherwise may easily occur, especially in continuous operation.

Having thus fully described the invention what is claimed as new and desired to be secured by Letters Patent is:

1. In a matrix-composing and type line-casting machine, in combination a vertically movable and guided composing key, resilient contact means associated with said composing key, mechanism for actuating said resilient contact means for insuring the return of the latter to its inoperative position.

2. In a matrix-composing and type line-casting machine in combination a vertically movable and guided composing key, a pair of spaced superposed resilient contact members associated with said key, mechanism for actuating said resilient contact members comprising a rotatable disc and a link operatively connecting the disc to the composing key, a cam on said disc adapted to engage one of said contact members for moving said contact member into operative engaging position during the depression of said composing key and spring means for returning said composing key to normal position, whereby said cam disengages said contact member for insuring the return of the latter to its inoperative spaced position.

3. In a matrix-composing and type line-casting machine, in combination a vertically movable and guided composing key, resilient contact.

means situated adjacent said composing key, mechanism for actuating said resilient contact means consisting of a pivoted circular disc having opposed flats, one of which rests on the upper surface of the adjacent resilient contact means when the latter is in inoperative position, a link pivoted at one end to said disc adjacent the other of said opposed flats and at its other end to the composing key, said link forming an articulated connection between the composing key and the circular disc, so that upon depressing the key the inner curved surface adjacent the flat nearest the contact means will bear against said contact means and press the latter into its operative position and spring means associated with the key for returning the key to its normal position whereby the curved surface of said disc moves away from said contact means for insuring the return of the latter to its inoperative position.

KURT BENDORFF. 

